Hearing protectors of the type which have two ear cups which are intended to enclose and seal about the ears of a wearer are previously known in a plurality of different variations. In order to ensure the sealing between the ear cup and the head of the wearer, the ear cup has, along its periphery, a sealing ring which is formable, possibly elastic, and which establishes a sealing abutment against the wearer's head, surrounding the wearer's ears. Normally, the sealing ring is manufactured from a foamed material, which is housed in a foil-like casing, which is that part of the sealing ring abutting against the head of the wearer.
By adapting the properties of the foamed material, optimization of the sealing ring may be made, both as regards sound damping, sealing and the feeling of more or less comfort in wearing the hearing protector. Thus, it has proved that a more rigid and hard sealing ring increases the sound damping properties of the hearing protector, but reduces the level of comfort for the wearer of the hearing protector. In addition, an excessively hard sealing ring can also jeopardize the sealing action between the sealing ring and the wearer's head, since an overly hard sealing ring is incapable of forming itself in adaptation to the head of the wearer to a sufficient degree.
As regards the perceived comfort when wearing a hearing protector, the ambient temperature is a major factor, since perspiration often occurs both interiorly in the hearing protector and between the sealing ring of the hearing protector and the skin or the wearer. Hence, excessive perspiration is perceived as unpleasant.
Another aspect concerning perspiration is that the hearing protector becomes dirty, and so should be cleaned at regular intervals, which is difficult or even impossible when foamed material is used in the sealing ring.
A further aspect in storage or use of hearing protectors at high ambient temperatures, for example if a hearing protector is left in a motor car or an airplane out in the sunlight, is that the high temperatures that prevail can considerably affect the material properties in the foamed material which is normally used in the sealing rings. A hearing protector heated in this manner can have completely different properties than those which were originally intended.
Other problems may occur in severe cold, where many foamed materials show a tendency to become excessively hard.
Hearing protectors are previously known in the art which display sealing rings of another type than the type under consideration here. Thus, U.S. Pat. No. 5,920,911 discloses a hearing protector where the above-considered sealing ring consisting of a foamed material has been replaced by a sealing ring that comprises a number of circumferential lamellae (designated lips) disposed in a radial direction with interspacing outside one another. These lamellae are produced from a resilient, possibly elastic material and have edge surfaces which are intended, under deformation, to sealingly abut against the wearer's head around the wearer's ear. These lamellae have attenuated edge portions facing towards the wearer's head, these portions constituting the actual contact surfaces against the wearer's skin. Such contact surfaces afford more or less only straight line contact against the skin, for which reason the abutment pressure may be considerable, with great risk that the hearing protector is perceived as uncomfortable already after only a short period of use.
In certain embodiments, there are disposed between the lamellae porous damping bodies produced from fibrous or foamed material, which would render an efficient cleaning of a hearing protector formed in this manner more or less impossible.
The present invention has for its object to design the hearing protector intimated by way of introduction such that the drawbacks inherent in the prior art technology are obviated. In particular, the present invention has for its object to realize a hearing protector where the sealing ring offers a high degree of comfort, combined with effective sealing and good sound damping. Further, the present invention has for its object to design the hearing protector according to the present invention such that a choice of materials is possible, which entails resistance also to greatly elevated temperatures. Finally, the present invention has for its object to realize a hearing protector where the sealing ring may be produced in a simple and economical manner and where it may simply be kept clean.
The objects forming the basis of the present invention will be attained if the hearing protector intimated by way of introduction is characterized in that the lamella, at least along its edge regions located most proximal the wearer's head, display portions which, in a direction towards the wearer, are arched from a central region in the sealing ring out towards its periphery.